The design of the fortepiano that I am playing is based on one from a late 18th century or very early 19th century made by Viennese builder, Anton Walter (1752-1826). Mozart admired the Walter piano for its expressive qualities, and actually owned one. This fortepiano was also built by the German builder Michael Walker. Its range is 5 octaves + 2 tones--from FF to g3. There are 2 strings per note in the lower octaves (from FF-A above middle C), with 3 strings per note in the upper octaves (from B-flat upwards); whereas on the modern piano, most of the range has 3 strings per note.